[bender]

It really depends on what you plan to do with it.

At the very least, I'd say you'll need the CVD driveshafts (front only is ok), slipper clutch, and swap the diff outdrives front to back - so the rear diff is all steel and the front diff has the plastic bits.

That would be my minimum.

For racing, you'll need to get rid of the shocks, probably run CVD's in the rear, and add turnbuckles to make adjustments easier. Next step would be to ditch the standard shock towers in lieu of some carbon-fibre items.